Sanaullah was critically injured when he was attacked by a fellow prisoner, police in Jammu on Friday, a day after Indian death row prisoner Sarabjit Singh died following brutal attack on him in a Lahore jail.

Pakistani prisoner Sanaullah being shifted to the intensive care unit at a hospital, in Jammu. HT/Nitin Kanotra

He received serious head injuries and was taken to the Government Medical College Hospital in Jammu, where doctors said he had slipped into a coma, much like Sarabjit Singh who was attacked in Lahore's Kot Lakhpat Jail on April 26 and died Thursday.

Pakistani prisoner Sanaullah is carried on a stretcher to be shifted to Chandigarh for treatment, after he was attacked by an inmate at a jail in Jammu. PTI

Police said Sanaullah was being tried for murder since the late 1990s for carrying out acts of militancy in Jammu and Kashmir.